The fabric of time and space is a fantastic way to imagine gravity and other potential wells;

XKCD

There’s a great video here: by an American physicist explaining how to set up the visualization, and then use a combination of weights and marbles to explain everything from gravity’s basic mechanics to how gravity lets us plot return trajectories from the moon.

In fact - here I am doing this very activity with the fantastic Ben Sparks (Ben Sparks | mathematician musician speaker) at a physics CPD event: